maxTaskSecond = int(input())
taskCnt = int(input())
taskArr = list(map(int, input().split()))
remainTask = 0
for task in taskArr:
    remainTask = max(remainTask + task - maxTaskSecond, 0)
res = len(taskArr)
while remainTask > 0:
    res += 1
    remainTask -= maxTaskSecond

print(res)
